Nope. They taught me about the secret of its Reconstruction and update integration. NOT easy... Unless they can help you. But still NOT easy to elaborate if without script.
xinso has been talking about which is a mandatory requirement of correct Reconstruction: Sessions.xml. It "IS" what you meant. Package? They are in Gailium119's 25398.1 and zwl29107's 26100 Edition Package.
At least it is the right thread for "Server Core with Desktop Experience", as you said this thread is for "Windows Reconstruction".
OP said Code: Windows Editions Reconstruction Project This is an educational project which aims to recreate internal or hardly available Windows editions from available resources using DISM only. so with this in mind i think this is the right thread... as my ServerAzureStackHCICor Desktop Experience Reconstruction is using Dism only.
what are you talking about there is no adding GUI package for ServerAzureStackHCICor as the Desktop Experience has to be taken and Reconstructed from available resources using DISM.
I know nothing about Sessions.xml modifications You have learned all that yourself, exploring the code?